Universal alternating current relay



Oct. .18, 1932. w. K. HOWE 1,882,845

UNIVERSAL ALTERNATING CURRENT RELAY Filed April 27, 1922 s Sheets-Sheet 1 PIC-31.2.

M ATTORNEY.

VE N TOR UNIVERSAL ALTERNATING CURRENT RELAY Filed April 27, 1922 5 Sheets-Sheet 2 w. K. HOWE 1,882,846

UNIVERSAL ALTERNATING CURRENT RELAY 3 Sheets-Sheet 3 Oct. 18, 1932.

Filed April 27, 1922 IIIIEIIIIW. 31m

3mg INVEN OR Zak c, fi m ATTORNEY Patented Oct. 18, 1932 UNITED STATES PATENT OFFICE VTIN'IHROP K. HOWE, OF ROCHESTER, NEW YORK, ASSIGNOR T0 GENERAL RAILWAY SIGNAL COMPANY, OF GATES, NEV' YORK, A CORPORATION OF NEW YORK UNIVERSAL ALTEIZNATING CURRENT RELAY Application filed. April 27,

This invention relates to relays for railway signaling purposes, and more particularly to polyphase, or two-element, relays of this kind.

The principal objects and purposes of the present invention are to construct a polyphase alternating current two or three-position relay, as conditions may require, which has very few moving elements, such elements being organized and arranged and connected together in a manner to increase the efficiency and reliability of their performance; to pro vide several types of motors, or electro-responsive devices, which may be readily interchanged; to provide anti-friction stops to limit the movement of the motor element; and to arrange and position the several parts in a casing having transparent walls in a manner to facilitate a clear and unobstructed line of vision through clearances betwee relatively moving parts, whereby the reduction of such clearances due to temperature changes, the accumulation of foreign matter or other causes, may readily be observed by inspection.

Various other objects and advantages of the improved relay will be pointed out the description progresses.

In describing the invention in detail, ref erence will be made to the accompanying drawings, in which Figure 1 is an end view of a relay embodying the present invention, parts thereof be ing broken away for clearness; I

Fig. :2 is a side view of the relay with the casing shown in section;

Fig. 3 is a diagrammatic and perspective view of the essential. elements of the relay embodying the present invention, portions thereof being shown separated in order to more clearly illustrate the construction of the d vice;

Fig. 4 is a diagrammatic lllustration of a typical block signal system employing relay embodying the present invention; and

Fig. 5 is a diagrammatic and perspective view of the essential elements of a relay having a modified form of electro-responsive device.

Referring to the accompanying drawings 1922. Serial No. 556,990.

a relay according to the present invention comprises, in general, a casing F, a circuit controller C supported from the top wall of the casing, and an electro-responsive device E supported in the bottom of the casing and operatively engaging said circuit controller. The structure of the relay casing F and the circuit controller C supported thereby is sub stant-ially the same as described in my prior application No. 397,227, filed July 19, 1920, which became Patent No. 1,710,664 on April 23, 1929, and therefore identical parts will only be briefly described.

The casing F comprises a skeleton framework having glass panels 1 on the sides thereof held in place by bezel rings 2 fastened to the framework by screws. The top plate 3 constructed of porcelain, slate or other suitable insulating material is fastened to the framework by screws 4, and serves as a terminal board and as a supporting means for the circuit controller C.

The relay is constructed so that the parts may be assembled in different ways to make up the various combinations or organizations of parts ordinarily required in practice in railway signaling systems. The construction illustrated provides for a three-position or two-position operation, with either one of several difierent kinds of electro-responsive devices, and with various contact arrangements.

In three-position operation the vane 34, which in relays of this type constitutes the power element, may be driven in either direction, depending upon the way in which its operating windings are energized; and consequently, some contacts may be closed when the relay is energized in one direction, and others when it is energized in the other direction, these different groups of contacts being commonly termed the normal and reverse contacts, and still other contacts which are closed when the relay is deenergized, conveniently termed neutral contacts, are also provided.

In two-position operation the vane 34 is driven in one direction and only one group of contacts is closed when the relay is energized, the other group of contacts being closed when the relay is deenergized. In both three-position and two-position operation, the contacts of the relay have deenergized positions to which they are biased by suitable counter-- weighting means, which tend to cause them to assume this position when current is cut off of the relay.

The top plate or terminal board 3 is provided with a large number of terminal or binding posts 6, some of which also serve as contact posts adapted to be engaged by the moving parts of the circuit controller C,

These terminal posts are arranged in rows, the two outside rows being provided with contacts on the inside of the relay which face downward, the second row of posts being provided with contacts facing upward. The next or third row of posts are known as heel posts and are provided with flexible connections 7 commonly known as pigtails, which are fastened to the movable contact fingers of the circuit controller; and the middle row of binding posts are provided as spares or reserves, some of which may be used to conduct current to the electro-responsive device, and the rest may be used in any manner found suitable in practice. These terminal or binding posts 6 are constructed and supported in a manner so that they may neither be turned nor removed from the outside of the casing as illustrated, thus making tampering with their adjustments impossible without breaking the seal 8 of the relay casin At opposite ends of the top plate are supported brackets 9 and 10 fastened to the top plate by screws. These brackets are drilled and split and provided with clamping screws for holding the trunnion pins 11. Pivotally supported on these trunnions is a carrier bar 12 having upturned ends, which is preferably made of aluminum or other suitable light and strong material. A plurality of contact fingers are fixedly carried by, but insulated from the carrier bar by insulating studs. These contact fingers may either be single or double, and they may either extend to one side of the carrier bar, or two such fingers may be integral and extend on opposite sides of said bar, as clearly illustrated in Fig. 3 of the drawings.

In providing a neural contact, that is, a contact which is closed when the relay s deenergized, a movable back contact, such as contact 13, and a movable front contact, such as contact 1 are electrically cennected together. The stationary contacts 15 an: 16 cooperating therewith are so adjusted that both of them are in contact when the relay is in its deenergized position, but that one or the otheris out of contact when the relay is energized in one dire tion or the other, the circuit to be closed by such neutral contact when the relay is deen ized being connected to the stationary contacts 15 and 16.

To the carrier bar 12 is adjustably fastened a hanger or operating lever 17. This hanger 17 is of general T shape, and is provided with a ridge extending therefrom, which serves as a fulcrum about which the hanger bar 17 may be adjusted with respect to the carrier bar 12 by supporting screws 19. The lower end of this hanger bar 17 is provided with a fork 20 adapted to be operatively engaged by any one of a number of suitable electro-responsivc devices.

The bracket 9 (see Fig. has integral therewith a projection having two forked extensions 21 adjacent to which are abutments 22. in these extensions are pivotally supported arms 23 by pins 24 passing through the forked extensions 21. These arms are curved at the inner end and normally, that is, when the carrier bar in its neutral position, abut against these abut ments 22. On the carrier bar is fastened a lifting bar 25, each end of the lifting bar being drilled and threaded to accommodate i' I- 1. Lne ao ustable lilting screws 2o, WillCll for three-position operation are preferably adjusted so that the particular electro-responsive device used is in its intermediate position when both of the arms 23 have their curved ends resting against the abutments 22, these liftin screws being further adjusted so that they just touch the arms 23 when curved ends thereof arein contact with the abutments. These lifting screws may then be locked in place by lock nuts 27.

lVhen this relay is to be used for twoposition operation, that is, is to be merely energized in one direction and deenergized, the lifting screws 26 are so adjusted that the vane is substantially in one extreme position when the relay is deenergized, thus closing one set of contacts, which may conveniently be called back contacts, and opening another set of contacts which may be called front contacts. If the relay is now energized, proper connection of the local and track, or line, phase having been made, the vane will be actuated substantially to the other extreme position, thereby closing the other or front contact. This change of adjustment of the lifting screws 26 facilitates the use of the whole vane for two-position operation, thus increasing the arc of movement, and correspondingly improving the operating characteristics of the relay.

To the bottom of the skeleton framework is fastened an electro-responsive device E, mounted on a base plate 28 having upstanding pedestals 29 fastened thereto by screws 30. The base plate 28 is fastened to the skeletpn frame F by screws 31, which have been snown with their heads on the inside of the casing. These screws 31 may, however, be made accessible from the outside of the easing, and may be checked against unauthorized tampering by sealing them in the usual manner. Adjacent the upper end of each of these pedestals 29 is provided an adjustable socket having a polished metal or jewel bearing 32 into which the ends of the relay spindle 33 are pivotally supported. This spindle 33 comprises two parts connected together by the usual form of flanged coupling members, and clamped between these coupling memhers is a vane 34 of electro-conductive material, for instance, such as aluminum, which constitutes the operating member of the relay. Adjacent the vane 34 the relay spindle 33 is provided with an off-set U-shaped portion 35 having upstanding ends in which a roller 36 is pivotally mounted eccentrically with respect to the axis of the relay spindle 33. This roller- 36 engages the fork 20 of the hanger or operating lever 17, thereby providing an operating connection between the electro-responsive device E and the circuit con troller C.

It will thus be observed that the roller 36 describes an arc of a circle as the vane 34 moves about the aXis of the spindle 33, thus causing the carrier bar 12 to be tilted in one direction or the other as the relay spindle 33 turns on its pivots. This roller 36 is of a diameter to fit loosely in the fork 20 of the hanger or operating lever 17 thereby pro- 'viding an anti-friction operating connection without bringing in undesirable lost motion.

The base plate 28 is provided with bosses 37 cast or otherwise constructed integral therewith. These bosses 37 are rabbeted and carry one of the field elements of the twoelement electro-responsive device. This field element comprises a ma gnetizable core 38 constructed of laminated transformer iron, and is fastened to the bosses by screws 39. This core 38 is provided with an air gap in the top portion arranged transversely thereof, through which the vane 34 is adapted to swing, and is also provided with coils 4O preferably connected in series. These coils mag netize the core 38 and cause a magnetic flux to penetrate the vane 34.

On each side of the vane 34 and directly over the core 38 supported by screws 41 and 42 extending into the upstanding lug 43 is a U-shaped core 44 with its back strap (the base portion of the U which connects up the two legs of the U) provided with a coil 45, which comprises the other field element of the relay. These U-shaped cores 44 are provided with enlarged pole pieces and are positioned so that the pole pieces face each other on opposite sides of the vane 34, and are disposed directly over and are symmetrically arranged with respect to the pole pieces formed by the air gap in the core 38. The coils 45 on the U-shaped cores are wound and connected in series in a manner that the magnetomotive-forces of the two cores are cumulative or additive, thus sending a magnetic flux through the vane 34 at two points in opposite direction.

On each side of and in the plane of the vane 34 is a bracket 46 suitably supported from the framework F of the casing. Each of these brackets 46 has riveted thereto a U-shaped member 4?, provided with inclined slots in which are slidably supported the projecting bearing studs 48 of stop rollers 49. hese stop rollers 49 are positioned so that one or the other, depending on the direction in which the vane 34 is moving, will be encountered by the vane and lifted and slid back thereby. thus serving as yieldable stop.

In practice the coils of the two elements energized by alternating currents of the same frequency, but which are displaced sufficiently in phase so that eddy currents produced in the vane 34 by one of these elements will be acted upon by the flux produced by the other element. This condition is most pronounced when the currents in these elements are in quadrature, or are displaced 9O electrical degrees. The production of a turning moment in the vane 34 is analogous to that of the well-known theory of polyphase induction motors, only that a shifting magnetic field is produced instead of a rotating one. This shifting field will shift in an arc starting at one of the poles of the top field element, then to the pole of the bottom held element, and then to the other pole of the top field element, thereby causing a torque to be produced. in the vane, by well-known principles of induction, in the direction of the are just referred to. Since this are is not concentric with the spindle, only a component of this torque would be effective. In order to cause this torque to act substantially perpendicular to the radii of the vane 34, slots 50 have been provided so that the eddy currents set up in the vane are compelled to flow substantially radially around the slots 50, thereby producing a torque about the spindle If the connecting wires to one of these field elements is reversed, the direction of shifting of the field is likewise reversed, and therefore the torque will tend to turn the vane in the opposite direction.

It is thus apparent that three-position operation of this relay is possible, by energiziug one phase constantly, and by energizing the other phase in either direction, and by deenergizing said latter phase.

In describing the operation of the relay when used as a three-position relay, attention directed to Fig- 4 which shows one typical arrangement of track and line circuits of a railway block signal system em ploying a three-position relay of this type. Although this relay may be used in many other well-known systems, for convenience onlv one such system has been illustrated.

The particular system illustrated is one of the type known as a polarized track circuit block signal system. In this type of system, a particular track circuit may have three conditions, namely, it may be energized with one relative instantaneous polarity, assuming the employment of alternating current, may be energized with the opposite instantaneous polarity, or may be deenergized. Obviously, if a two-element, or two-phase, alternating current relay is used, three kinds of indication may be obtained. The track rails 51 are divided into blocks by insulating oints 52 in the usual manner, the block I and the adjacent ends of two other blocks H and J being shown. The parts and circuits associated with the various blocks are the same, and for convenience have been given like reference characters with distinctive exponents. Although any type of signals may be used, the usual fixed signals S have been illustrated. These signals S are provided with the usual motors, gearing, hold-clear devices and circuit controllers, all organized and arranged to cause the signal to gravitate to the zero position when deenergized, to cause it to be actuated to the degree or caution position when the 45 degree circuit is energized, and to assume the 90 degree or clear position when the 90 degree circuit is energized.

The 90 degree circuit may be traced as follows :-l5eginning at the secondary winding 62 of the transformer P, wires 75 and 53, stationary contact 54, 90 degree wire 55, through the signal S and mechanism associated therewith, through wires 56 and 57 back to winding 62 of the transformer P. It should be noted that this circuit is only closed when the relay is energized in one direction, whereas the 45 degree circuit is energized when the relay is energized in either direction. Consequently, if the relay is in its normal or clear position illustrated, and wire should be broken at this time, the signal S would assume the 45 degree position by reason of the 45 degree circuit. This 45 degree circuit may be traced as follows :Beginning at the secondary winding 62 of the transformer P, Wires 75 and 53, stationary contact 58 or 59, depending on the instantaneous polarity of the track circuit actuating the relay, 45 degree wire 60, through the mechanism associated with the signal S, through wires 56 and 57 back to winding 62.

Each of the blocks is provided with a source of alternating current which is supplied through aquick acting or snap polechanger switch SC controlled by the signal S one block in advance of the track circuit, the instantaneous polarity of this current depending upon the condition of the next block in advance. This source of alternating current 18 connected to suitable transformers P transmitting circuits, illustrated by line wires 61, supported on suitable poles and insulators (not shown). These transformers P supply alternating current to track circuit transformers T, as illustrated.

The encrgization of the 45 degree and 90 degree circuits above traced, depends on whether the track phase of the track relay is energized at all, and if so, what the instantaneous polarity as compared with the instantaneous polarity of the local phase is. The instantaneous polarity of the alternating current in the track phase depends upon the position of the snap pole-changer switch S0 associated with the signal one block in advance of the block in question. This pole changer switch is quick acting, and is actuated by that signal at some position of the signal blade below the 45 degree position, and is usually and preferably, actuated at about the 40 degree position.

The circuit for energizing the track phase winding 45 of the track relay under normal conditions may be traced as follows :Beginning at the secondary winding 72 of transformer T wire 63 contact 64 of snap polechanger switch SC wire 65 track rail 51, wire 66, winding 45 of the track relay, wire 67, track rail 51, wire 68 contact 69 wire 70 variable impedance 71 back to winding 72 The circuit for energizing the local phase 40 of the relay may be traced as follows Beginning at the secondary winding 73 of the transformer T, wire 74, local phase 40 of the track relay, wire 76 back to the winding 73.

Assuming the trackway circuits to be in their normal or clear condition as illustrated in Fig. 4, and that a train is moving in the block H in the direction of the arrow. As the train enters the block I the track phase 45 of the three-position relay will be shunted by the axles and wheels of the train, thus causing the relay to assume its neutral or deenergized position, thereby causing the carrier bar 12 to assume its horizontal position and open the 45 degree and 90 degree control circuits of the signal S. This will cause the semaphore of the signal S to gravitate to the zero position, and during this movement when it passes about the 40 degree position the snap pole-changer switch SC will be thrown over, thereby reversing the polarity of the current flowing in the track circuit H.

Assuming now that the train has passed into the block J, thus bringing the signal S to the zero degree or danger position, and throwing over the snap pole-changer switch SC substantially in the same manner as just described in connection with a signal at the entrance of the block I, thus reversing the polarity of the current in the track circuit of the block I. This reversal of the polarity of the current in the track circuit of the block I causes the track relay to be energized to cause a torque in the opposite direction to that of the torque under normal conditions, thus causing the contact fingers to move to the opposite position, and closes the 45 degree circuit but not the 90 degree circuit. This will cause the signal S to be actuated to its 45 degree position, thereby again reversing the snap pole-changer switch SC back to its original position, thereby energizing the track circuit of the block H to its normal relative polarity, that is, to cause the signal at the entrance block ii to indicate clear.

Assuming now that the train has passed out of the block J, thus causing the signal S to assume its 45 degree position and during such movement cause the snap polechanger switch SC to be thrown back to its original or normal position, thus reversing the polarity of the current in the track circuit of the block I back to normal. The current now flowing in the track phase winding 45 of the relay will cause it to produce a torque in the opposite direction to that just mentioned, thereby causing the movable contacts to assume the other extreme position closing both the 45 degree and 90 degree circuits of the signal S, and cause it to assume its normal position.

Although either the upper or the lower induction element of the electro-responsive device may be employed as the local phase element, the upper element is preferably employed for this purpose. In order to get a desired phase displacement between the currents flowing in these two elements, a suitable resistance may be inserted in the circuit of the line or track phase, and when the relay is employed as a track relay this variable resistance or impedance 71, as conditions may require, may be inserted at the opposite end of the track circuit, as shown, thus limiting the current when a train stands over the transformer, and also red cing the voltage between the rails to the extent of the voltage drop across the inserted resistance or impedance.

In Fig. 5 ms been illustrated a modified form of electro-responsive device for actuating the contact bar 12 of the circuit controller C. This device is in many respects similar to the one illustrated in Figs. 1, 2 and 3, and therefore the diiferences, rather tl an the whole structure, will be described in detail. In this embodiment of the invention, a larger arc of movement is obtained by constructing the vane 80 to span a larger angle, thus increasing the energy output during each actuation. Balancing weights are provided on the spindle 33 located on opposite sides of the vane 80. These balancing weights comprise threaded studs 81 extending perpendicularly from the spindle 33 but at an angle to each other, and provided with adjustable weights comprising washers 82 held between nuts 83 threaded on the studs 81, thus facilitating the balancing of the vane 80 in two different planes, thereby allowing a perfect balance to be obtained.

In this embodiment of the invention, a simplified arrangement of field elements is used. One of these elements comprises a U-shaped core 85 provided with a coil 86, and the other element comprises a three-legged magnet core 87 having a coil 88 on its middle leg. These cores are constructed in the usual maner to reduce the How of eddy currents by building them up of laminated iron. These elements are mounted on opposite sides of the vane, in a manner so that the five poles formed by the two elements are in staggered relation. It has been found in practice that when only the element having a U-shaped core 85 is energized, that a small torque is produced tending to cause operation of the relay. Such operation of devices of this kind is commonly known as creeping. Such creeping is practically unnoticeable if the other, or three-legged element 87, is alone energized. It has, therefore, been proposed to use the element having a three-legged core 87 as the local phase of the relay.

In railway signaling, due to the limitations encountered in track circuits, it is desirable to supply the larger part of the energy by the local phase of the track relay, and in order to do this when using a three-legged field element as the local phase element without undue heating of the coil, it has been found expedient to construct the three-legged element in the peculiar form illustrated. This three-legged element more specifically comprises a back yoke 89 having a middle leg 90 terminating in an enlarged pole piece 91, and having two outside legs 92 terminating in sloping extensions 98 adj acent the pole piece 91. This construction affords a large amount of space to receive the coil 88, and at the same time allows the ends of the legs to come close together, thereby reducing the size of the vane and other field elements, with which it is to cooperate. This three-legged element is supported by four posts 94 cast integral with the base plate 95, this base plate 95 being constructed interchangeably with the base plate 28, thus facilitating the substitution of one electro-responsive device for the other. The other element is provided with a supporting plate 96 screw fastened to similar posts 97 also cast integral with the base plate 95.

Assuming now that the relay embodying this invention, that is, either the first or second form, has its field element energized with currents which are out of time phase relation with the other. This causes the flux, due to one of the elements, to act on the eddy currents induced in the vane by the other element, thus causing a torque to be applied to the hanger bar 17 through the action of the eccentrically supported roller 86 acting on the forked end 20 of the hanger bar 17.

Assuming the torque of the vane to be clockwise. The contact bar 12 will be moved counter-clockwise, thus causing the contact finger 14 to move upward to engage the stationary Contact 16. If one of the phases is now reversed, the torque in the vane will be in the other direction, and the contact finger 13 will engage the bottom stationary contact 15, all of which is obvious from the drawings. If one of the phases of the relay is deenergized the torque will subside, and the relay will assume its neutral position, thereby closing only the neutral contacts.

While I have described several specific forms of my invention, and have shown how the invention may be employed in connection with one specific arrangement of trackway circuits for automatic block signal systems, I desire to have it understood that the particular construction shown and described may be modified and adapted in many respects to suit the particular working conditions encountered without departing from the scope of the present invention.

What I claim as new and desire to secure by Letters Patent, is

1. A relay comprising, a casing including a top and a bottom plate, a carrier bar supported on a horizontal axis in said casing and carried from the top plate and provided with contact fingers, a forked hanger extending from said bar, and an electro-responsive device carried by the bottom plate and having a spindle mounted substantially parallel with said carrier bar and provided with an eccentrically disposed roller continuously in engagement with the fork of said hanger.

2. In a relay, the combination of an electro-responsive device comprising, a base, induction elements supported on said base to form an air gap, a vane pivotally supported 7 over said elements traversing said air gap when moving about its pivotal axis, a casing having oppositely disposed glass walls, said electro-responsive device being supported in said casing in a manner so that the glass walls "1 provide an unobstructed line of vision through opposite walls of said casing and the entire air gap.

3. A relay comprising, a box-like casing, stationary contacts in the top of said casing,

a carrier bar having contact fingers supported on a horlzontal axis in the top of said casing, a spindle having a vane depending therefrom and supported from the bottom of said casing to be substantially parallel to 'said carrier bar, induction elements associated with said vane, and a detachable constantly engaging inter-engaging operating connection between said bar and spindle.

4. A relay comprising, a box-like casing having glass side walls and a top plate of insulating material, circuit controlling means ling means and said spindle.

5. In a relay, a casing, a carrier bar pivoted in the casing, contact fingers on the carrier bar, induction elements in the casing, a horizontal spindle pivoted in the casing, a vane on the spindle cooperating with the induction elements, a fork depending from the carrier bar, and an operating connection, with constant rolling contact, between the fork and spindle for rocking the carrier bar.

6. In a relay, a casing, a top plate, a carrier bar pivoted centrally of the plate, contact fingers on the bar extending to either side of the same, fixed contacts on the plate cooperating with the fingers, a fork depending from the carrier bar, induction elements in the casing, a horizontal spindle pivoted in the casing, a vane on the spindle cooperating with the induction elements, and a c011- tinuously engaging, detachable, operating connection between the fork and the spindle for rocking the carrier bar.

7. In a relay, a casing, a top plate for the casing, a carrier bar pivoted to the top plate, Contact fingers mounted on the carrier bar,

a bottom plate, a vane pivoted to the bottom plate, an operating connection between the vane and the carrier bar, a two legged core at one side of the vane, a 0011 on the core and a three legged core at the other side of the M vane, the middle leg having an enlarged pole face, the two outer legs being of substantially constant cross section throughout and bent inwardly at their free ends toward the middle leg to constitute pole faces, and a coil on the middle leg and between the outer legs.

8. A relay for railway signalling purposes comprising, two oppositely disposed cores having legs terminating in pole faces facing each other and spaced a distance to form an air gap, one of said cores havin two legs with enlarged pole faces disposed nearer each other than are the legs and the other core having three legs the middle one of which has an enlarged pole face and the two outside legs of which are of substantially constant cross section throughout and extend diagonally toward each other to form pole faces disposed very closely to the middle leg, a winding on the back yoke of said two legged core and another winding on the middle leg of said three legged core, whereby if alternating currents of the same frequency but displaced in phase are applied to the windings a shifting field of flux and a resulting torque is produced in said vane.

9. In a relay, a casing, a top plate, a carrier bar pivoted to the top plate, a bottom plate, a vane pivotally carried by the bottom plate on a horizontal axle, a motor means for the vane, an operative connection between the axle and carrier bar, and an adjustable counter-weight on the axle to one side of the median plane through the vane and axle whereby to permit adjusting the vane load curve characteristics.

10. In a relay, a casing, a top plate, a carrier bar pivoted to the top plate, a bottom plate, a vane pivotally carried by the bottom plate on a horizontal axle, a motor means for the vane, an operative connection between the axle and carrier bar, counterweights, adjustable in amount and radially in position, carried by the axle on opposite sides of the median plane through the vane and axle.

11. In a relay, a casing, an insulating top plate on the casing, a bottom plate on the casing, a carrier bar pivoted to the top plate,

a vane pivotally carried by the bottom plate,

a motor means for the vane, a hanger adjustably connected to the carrier bar, and an operative connection between the hanger and the vane.

12. In a relay, a casing, an insulating top plate on the casing, a bottom plate on the easing, a carrier bar pivoted to the top plate, a motor means for the vane, a vane pivotally carried by the bottom plate, a motor means for the vane, a hanger having a knife edge bearing against the carrier bar means for connecting the hanger to the carrier bar and adjusting it about its knife edge relative to the carrier bar, and an operative connection between the hanger and the vane.

13. In a relay, a top plate, contact means carried therefrom, a casing, a bottom plate for the casing, supports fixed to the bottom plate, a horizontal spindle carried by the supports, brackets fixed to the bottom plate, induction elements on the brackets arranged to form an air gap, a vane operable in the air gap and carried by the spindle and an operative connection between said contact means and said vane.

14;. In a relay, a casing, a spindle pivotally mounted in the casing, a swinging vane fastened to said spindle, and a stop member for said vane including, a slotted plate fixed to said casing, with the slot inclined upwardly, and a roller slidably carried in the slot and in the path of movement of said vane.

15. In a relay, a casing, a spindle pivotally mounted in the casing, a swinging vane fastened to said spindle, and a stop member for said vane including, a U-shaped slotted plate fixed to said casing, with the slot inclined upwardly, and a roller slidably trunnioned in the slot and in the path of movement of said vane.

16. In a relay, in combination, a casing, a

spindle pivotally mounted in said casing, a swinging vane fastened to said spindle, and a stop member for said vane comprising, a carrier fixed to said casing, and a roller supported by said carrier, in the path of movement of said vane, so as to be rotatable and slidable in an upwardly inclined direction, whereby to absorb kinetic energy of the vane.

In testimony whereof I hereby afiix my signature.

VVINTI-IROP K. HOWE. 

